![\"Fog](\"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-content\/uploads\/sites\/5\/2010\/03\/fog_prod.gif\")
<\/a><\/p>\nFigure 1: GOES-11 fog product for 8 UTC 2 March 2010.<\/span><\/p>\n Identification of liquid water cloud layers that have temperatures below freezing is important for aviation safety. Brightness temperature differencing two channels may be used to identify liquid water cloud layers. Figure 1<\/strong> (above)shows the channel difference between 3.9 and 10.7 \u00b5m from GOES-11 prior to sunrise. A liquid water cloud layer (white) is evident over Nebraska, western Kansas, and western Oklahoma. <\/span><\/span><\/span> <\/p>\n Figure 2: GOES-11 (10.7-12.0) \u00b5m channel difference for 17 UTC 2 March 2010.<\/p>\n \n Nine hours later, the channel difference between 10.7 and 12.0 \u00b5m from GOES-11 (Figure 2<\/strong> – above)\u00a0 indicates the same cloud liquid water cloud layer over central Nebraska and northern Kansas(red). MODIS imagery also captured the same cloud layer at 830 UTC at 3.9 \u00b5m (Figure 3 – <\/strong>below). Brightness temperature differences of MODIS imagery between 8.53-11.02 \u00b5m (Figure 4 – <\/strong>below) and 8.53-12.03 \u00b5m (Figure 5 – <\/strong>below) are unable to reveal the cloud layer. This is due to the lack of contrast between the liquid water cloud and the surrounding ground. <\/span><\/p>\n <\/span> Figure 3: Modis 3.9 \u00b5m at 830 UTC 2 March 2010.<\/p>\n \n Figure 4: Modis 8.53 \u2013 11.02 \u00b5m for 830 UTC 2 March 2010.<\/p>\n \n Figure 5: Modis 8.53 \u2013 12.3 \u00b5m for 830 UTC 2 March 2010.<\/p>\n \n However, brightness temperature differences of MODIS imagery between 11.02 \u2013 12.03 \u00b5m does reveal the liquid water cloud layer (Figure 6 – <\/strong>below). These examples highlight the benefit of channel differencing to identify liquid water cloud layers. When this information is combined with the GOES-11 skin temperature (Figure 7 – <\/strong>below), one can see that the liquid water cloud layer, shown in the above figures, has a cloud top temperature below freezing. This may be valuable information to those concerned with icing potential of aircraft.<\/p>\n \n Figure 6: Modis 11.02 \u2013 12.3 \u00b5m for 830 UTC 2 March 2010.<\/p>\n \n <\/span><\/p>\n J. Braun and Louis Grasso Figure 1: GOES-11 fog product for 8 UTC 2 March 2010. Identification of liquid water cloud layers that have temperatures below freezing is important for aviation safety. Brightness temperature differencing two channels may be used to identify liquid water cloud layers. Figure 1 (above)shows the channel difference between 3.9 and Continue Reading<\/a><\/p>\n","protected":false},"author":43,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,47,17,28],"tags":[60,80,102,137,156,187],"class_list":["post-160","post","type-post","status-publish","format-standard","hentry","category-aviation-weather","category-geostationary-satellite-discussion","category-icing","category-satellites","tag-aircraft","tag-channel","tag-differencing","tag-goes-11","tag-icing","tag-modis"],"_links":{"self":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts\/160","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/users\/43"}],"replies":[{"embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/comments?post=160"}],"version-history":[{"count":1,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts\/160\/revisions"}],"predecessor-version":[{"id":6167,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/posts\/160\/revisions\/6167"}],"wp:attachment":[{"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/media?parent=160"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/categories?post=160"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rammb2.cira.colostate.edu\/visit-blog\/wp-json\/wp\/v2\/tags?post=160"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}<\/a><\/span><\/span><\/span> <\/span><\/span><\/span> <\/span><\/span><\/span> <\/span><\/span><\/span> <\/span><\/span><\/span> <\/span><\/span><\/span> <\/span><\/span><\/span> <\/span><\/span><\/span><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a>
\nFigure 7: GOES-11 skin temperature at 17 UTC 2 March 2010.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"